The present invention relates to a FAX-through data network and a remote access appliance control apparatus and method. In particular, the invention utilizes a data network to transfer a FAX data packet or an appliance control packet to a FAX machine or an appliance, respectively. The present invention discovers the capability to share an internet protocol (IP) address of a LAN end station and the ability to intercept network data packets transmitted to the LAN end station in order to identify a FAX data packet or an appliance control packet.
A FAX transmission using the public switched telephone network (PSTN) is processed with the same methodology as a voice telephone connection. To transfer a document via FAX, the transmitting FAX machine starts up a connection request by dialing a receiving party""s telephone number. The PSTN acts both as a destination locator and a channel provider with two tasks. First, the PSTN will find the destination FAX location and alert the receiving FAX to answer the transmission request. Second, the PSTN will make a channel connection between the transmitting FAX and the receiving FAX.
As depicted in FIG. 1, there is no difference to the PSTN whether handling a FAX or a voice telephone connection. Due to the fact that a real time response in a conversation between two parties is required, the cost of the connection is measured by the duration of the connection and the distance between the two parties. This cost measurement is set mostly because a voice conversation requires a real time response since the human ear and brain can only tolerate a small amount of latency.
This cost measurement is, however, inappropriate for FAX transmissions since a real time response, measured in 0.1 seconds of time, is not required. Furthermore, the cost measurement of the duration of the connection is not particularly appropriate. A human conversation always exchanges information at a constant rate. Therefore, the conversation always takes the same amount of time to get a message across. In other words, the connection time equals the amount of information exchanged. On the other hand, a FAX communication can utilize a faster data rate than the data rate used by voice communications (when channel bandwidth is available) or slow down the data rate when channel traffic is congested. In addition, a latency in the response time on the order of one or more minutes is tolerable for FAX transmissions. As such, a correct method for measuring the cost of FAX communication is a measurement of the transferred data size instead of the call duration, provided the channel bandwidth is scalable. In summary, FAX customers pay expensive PSTN toll charges for a service which is not needed.
In recent years, the bandwidth of data network connections between two end user computers or two end station computers has expanded to meet the data transfer requirements discussed above. These data networks are readily available in every trade industry and business. Data networks have imposed larger latency compared to the PSTN, but it is acceptable when dealing with FAX transmissions. In addition, the cost of the data transfer is measured by the size of the exchanged information in many cases. For example, a 56K modem connection can transfer 56 Kbits of information per second (560K bit per 10 second or 201,600 Kbit per hour) free of charge in a global data network, the Internet. In fact, other data network connection technologies can provide even higher bandwidth. Consequently, since the average size of a FAX communication is about 480K, the cost of a FAX transmission over a data network is negligible (free of charge).
Based on the argument described above, FAX services utilizing data networks should be quite common. In reality, there are very few such deployments. The reason is due to the fact that data networks were not fully deployed until recently. Moreover, FAX machines based on the PSTN have dominated the market for more than three decades. FAX equipment vendors have no incentive to move over to data networks because the cost of FAX transmissions are paid by the end user, not by the equipment vendor.
As depicted in FIG. 2, a data network topology is comprised of multiple local area networks (LAN) connect together by a giant, a wide area network (WAN), the Internet. Within a LAN, there are multiple End stations connected thereto. Each end station is assigned a unique identification number referred to as its Internet Address or the IP address. Any data exchanged between two parties will need to identify the destination or end station location by its corresponding IP address. The connection between the LAN and the WAN is separated by a Router, which will relay the data to the WAN if the destination IP address is not within the LAN.
The data network also uses a session port to identify the type of application. There are xe2x80x9cwell knownxe2x80x9d session port numbers which are fixed in the Internet to represent application flow. For example, the hyper text transfer protocol (HTTP) uses session port 80, while electronic mail (E-Mail) uses session port 110. On the other hand, there are a few unassigned session ports available for individual applications. Since there are many application communications in the data network, a session port attached to a transmitting data package in the network will enable the receiving party to identify and process the data package in order to collect the information in the data package.
FIG. 3 depicts one technique for utilizing a data network in the FAX transmission process. This type of service establishes a central FAX-network server which connects one end to the PSTN and the other end to the data network. Each receiving customer will be given a unique PSTN telephone number for the FAX-network server to identify the destination. Users are also required to have an E-Mail address in order to receive the electronic form of the FAX transmission which is sent through the unique PSTN number.
The transmitting party is required to make a PSTN call to the central FAX-network server. Although, the dialed PSTN number is used to uniquely identify the FAX receiver, the FAX number is physically connected to central FAX-server through the PSTN network which is similar to a corporation direct line. The FAX-network server will then receive the FAX data and put it in a temporary storage. The transmitting party performs the same operations as a normal call through the PSTN since it dials and faxes through a regular telephone number.
The FAX-network server perform two tasks. First, it identifies the receiving PSTN number and maps it to the E-Mail address of the receiving party. Then, it retrieves the stored FAX data, repackages the data into a data network format and sends the data through the data network to the individual E-Mail address. The receiving party can retrieve the E-Mail and either view the FAX document in an electronic format or as the printer""s printout.
The problem with this method is that it requires the transmitting party to place a PSTN toll call to the central FAX-network server. Therefore the toll cost for the call is not reduced if the distance between the sender and the receiver is shorter than the distance between the sender and the central server. Moreover, this method provides only a conversion from the FAX information to the electronic format without a reduction in cost. In addition, this technique does not provide a good solution for receiving a FAX from a heritage FAX machine.
FIG. 4 depicts an additional FAX system which utilizes a data network to deliver a FAX communication. This method requires the transmitting FAX to place a PSTN call to its local FAX-network server, similar to the previous method. However, instead of using a central FAX-network server to receive the incoming FAX communication, this method sets up multiple regional FAX-network servers to reduce the long distance telephone toll charge. The local or regional FAX-network server will receive and store the FAX communication in a temporary data buffer. This local server then repackages the FAX communication into a data network format and forwards it to a remote FAX-network server which is closer to the receiver FAX. The remote FAX-network server will unpack the FAX communication to restore the information into the original FAX format and make a FAX telephone call through the PSTN to the receiving FAX machine. Finally, the receiving FAX machine will get the FAX communication, without the cost of a direct long distance call from the sender to the receiver. The receiver""s PSTN telephone number must be registered in all the servers in order for the technique to function. For the local server, the receiver""s PSTN telephone number will be used to locate the proper remote-server to which the FAX communication should be sent. For the remote server, the receiver PSTN telephone number is used to make a PSTN toll call from the remoter server to the receiving FAX machine.
Although this technique eliminates the long distance toll charge by using a data network, the technique suffers from two drawbacks. First, the requirement of setting up several possible regional/local FAX-network servers is costly. Second, the regional/local PSTN toll cost in many sub-urban areas will still be charged a fee.
FIG. 5 depicts a further FAX system which also utilizes a data network to deliver a FAX communication. Each FAX machine is required to connect to a PBX emulator that converts the FAX communication to data network format. Each PBX emulator is connected to an end station having a unique IP address. Each end station performs full network protocol and application functions in order to send and receive data network packets containing the FAX communication. This implementation also requires each end station to construct a full data base that contains a mapping table which can map PSTN telephone numbers to data network IP addresses.
One problem with this technique is that each end station is required to have a dedicated IP address which is a precious resource of the Internet. In addition, the end stations need to perform full network protocol operations which are extremely complicated in comparison to a simple FAX transfer. This results in an overly complicated consumer application. Moreover, since each end station has a dedicated IP address and performs full network protocol functions, the network administration system is required to performs maintenance and administration routines for the end station which further consumes administrator resources. In effect, the complexity required to implement the end stations renders this technique cost ineffective.
What is needed is a technique for a FAX transmission system that utilizes a FAX-through data network without requiring a plurality of regional/local FAX-network servers. In addition, a need remains for a technique that eliminates the use of the PSTN. Also, there is a need for a low cost implementation that does not require assignment of an internet address to users in order to utilize the invention and receive FAX communications.
The present invention overcomes the identified problems by providing a FAX-through data network and remote access appliance control apparatus and method. In particular, the invention utilizes a data network to transfer a FAX data packet or an appliance control packet to a FAX machine or an appliance, respectively. The present invention discovers the capability to share an IP address of a LAN end station and the ability to intercept network data packets transmitted to the LAN end station in order to identify a FAX data packet or an appliance control packet.
An exemplary embodiment of the apparatus includes a receiver side LAN end station having a receiver IP address and a sender side LAN end station having a sender IP address. A first converter receives the FAX communication from the sender FAX and converts the FAX communication to a network packet format to generate a FAX packet. The FAX packet includes a predefined session port number and a receiver FAX-network ID. A FAX-network server receives the FAX packet, extracts the receiver FAX-network ID, performs a lookup of a corresponding destination IP address in a mapping table and forwards the FAX packet to the destination IP address. A second converter intercepts and identifies the FAX packet, extracts the FAX communication from the FAX packet, establishes a communication link with the receiver FAX without routing a signal through the PSTN and transmits the FAX communication to the receiver FAX machine.
In an embodiment for asserting a control command to an appliance from a remote network user, the invention includes an appliance side LAN end station having an appliance IP address which is shared by the appliance. An appliance control packet is generated by the remote network user and includes a predefined session port number, an appliance network ID and the control command. An appliance network server receives the appliance control packet, extracts the appliance network ID, looks-up a corresponding destination IP address in a mapping table, and forwards the appliance control packet to the destination IP address. An appliance converter intercepts and identifies the appliance control packet, extracts the control command and asserts the control command to the appliance using an appliance communication protocol.
The invention provides many advantages over known techniques. The present invention includes the ability to share the IP address of a LAN end station, thereby eliminating the need for additional IP addresses. This feature results in apparatus wherein each individual FAX is not required to assume full data network communication protocol operations, which are left to the LAN end station. Consequently, network administration effort required to manage additional FAX devices is negligible. In addition, the invention also eliminates local and long distance toll cost charges for FAX transmissions which can become extensive. Moreover, the invention allows remote access control of appliances which promotes the mobility that is now so prevalent in our society.